From: Kristina Martsenko <kristina.martsenko@arm.com> To: linux-arm-kernel@lists.infradead.org Cc: Adam Wallis <awallis@codeaurora.org>, Amit Kachhap <Amit.Kachhap@arm.com>, Andrew Jones <drjones@redhat.com>, Ard Biesheuvel <ard.biesheuvel@linaro.org>, Arnd Bergmann <arnd@arndb.de>, Catalin Marinas <catalin.marinas@arm.com>, Christoffer Dall <christoffer.dall@arm.com>, Dave P Martin <Dave.Martin@arm.com>, Jacob Bramley <jacob.bramley@arm.com>, Kees Cook <keescook@chromium.org>, Marc Zyngier <marc.zyngier@arm.com>, Mark Rutland <mark.rutland@arm.com>, Ramana Radhakrishnan <ramana.radhakrishnan@arm.com>, "Suzuki K . Poulose" <suzuki.poulose@arm.com>, Will Deacon <will.deacon@arm.com>, kvmarm@lists.cs.columbia.edu, linux-arch@vger.kernel.org, linux-kernel@vger.kernel.org Subject: [RFC 14/17] arm64: unwind: strip PAC from kernel addresses Date: Fri, 5 Oct 2018 09:47:51 +0100 [thread overview] Message-ID: <20181005084754.20950-15-kristina.martsenko@arm.com> (raw) In-Reply-To: <20181005084754.20950-1-kristina.martsenko@arm.com> From: Mark Rutland <mark.rutland@arm.com> When we enable pointer authentication in the kernel, LR values saved to the stack will have a PAC which we must strip in order to retrieve the real return address. Strip PACs when unwinding the stack in order to account for this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> --- arch/arm64/include/asm/pointer_auth.h | 10 +++++++--- arch/arm64/kernel/ptrace.c | 2 +- arch/arm64/kernel/stacktrace.c | 3 +++ 3 files changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 5e40533f4ea2..e60f225d9fa2 100644 --- a/arch/arm64/include/asm/pointer_auth.h +++ b/arch/arm64/include/asm/pointer_auth.h @@ -55,12 +55,16 @@ static inline void ptrauth_keys_switch(struct ptrauth_keys *keys) * The EL0 pointer bits used by a pointer authentication code. * This is dependent on TBI0 being enabled, or bits 63:56 would also apply. */ -#define ptrauth_pac_mask() GENMASK(54, VA_BITS) +#define ptrauth_pac_mask_ttbr0() GENMASK(54, VA_BITS) + +#define ptrauth_pac_mask_ttbr1() (GENMASK(63, 56) | GENMASK(54, VA_BITS)) -/* Only valid for EL0 TTBR0 instruction pointers */ static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr) { - return ptr & ~ptrauth_pac_mask(); + if (ptr & BIT_ULL(55)) + return ptr | ptrauth_pac_mask_ttbr1(); + else + return ptr & ~ptrauth_pac_mask_ttbr0(); } #define ptrauth_task_init_user(tsk) \ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index cb8246f8c603..bf4d6d384e4f 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -970,7 +970,7 @@ static int pac_mask_get(struct task_struct *target, * depending on TCR_EL1.TBID*, which we may make use of in future, so * we expose separate masks. */ - unsigned long mask = ptrauth_pac_mask(); + unsigned long mask = ptrauth_pac_mask_ttbr0(); struct user_pac_mask uregs = { .data_mask = mask, .insn_mask = mask, diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index 4989f7ea1e59..44f6a64a8006 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -24,6 +24,7 @@ #include <linux/stacktrace.h> #include <asm/irq.h> +#include <asm/pointer_auth.h> #include <asm/stack_pointer.h> #include <asm/stacktrace.h> @@ -56,6 +57,8 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp)); frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8)); + frame->pc = ptrauth_strip_insn_pac(frame->pc); + #ifdef CONFIG_FUNCTION_GRAPH_TRACER if (tsk->ret_stack && (frame->pc == (unsigned long)return_to_handler)) { -- 2.11.0
WARNING: multiple messages have this Message-ID (diff)
From: kristina.martsenko@arm.com (Kristina Martsenko) To: linux-arm-kernel@lists.infradead.org Subject: [RFC 14/17] arm64: unwind: strip PAC from kernel addresses Date: Fri, 5 Oct 2018 09:47:51 +0100 [thread overview] Message-ID: <20181005084754.20950-15-kristina.martsenko@arm.com> (raw) In-Reply-To: <20181005084754.20950-1-kristina.martsenko@arm.com> From: Mark Rutland <mark.rutland@arm.com> When we enable pointer authentication in the kernel, LR values saved to the stack will have a PAC which we must strip in order to retrieve the real return address. Strip PACs when unwinding the stack in order to account for this. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com> --- arch/arm64/include/asm/pointer_auth.h | 10 +++++++--- arch/arm64/kernel/ptrace.c | 2 +- arch/arm64/kernel/stacktrace.c | 3 +++ 3 files changed, 11 insertions(+), 4 deletions(-) diff --git a/arch/arm64/include/asm/pointer_auth.h b/arch/arm64/include/asm/pointer_auth.h index 5e40533f4ea2..e60f225d9fa2 100644 --- a/arch/arm64/include/asm/pointer_auth.h +++ b/arch/arm64/include/asm/pointer_auth.h @@ -55,12 +55,16 @@ static inline void ptrauth_keys_switch(struct ptrauth_keys *keys) * The EL0 pointer bits used by a pointer authentication code. * This is dependent on TBI0 being enabled, or bits 63:56 would also apply. */ -#define ptrauth_pac_mask() GENMASK(54, VA_BITS) +#define ptrauth_pac_mask_ttbr0() GENMASK(54, VA_BITS) + +#define ptrauth_pac_mask_ttbr1() (GENMASK(63, 56) | GENMASK(54, VA_BITS)) -/* Only valid for EL0 TTBR0 instruction pointers */ static inline unsigned long ptrauth_strip_insn_pac(unsigned long ptr) { - return ptr & ~ptrauth_pac_mask(); + if (ptr & BIT_ULL(55)) + return ptr | ptrauth_pac_mask_ttbr1(); + else + return ptr & ~ptrauth_pac_mask_ttbr0(); } #define ptrauth_task_init_user(tsk) \ diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index cb8246f8c603..bf4d6d384e4f 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -970,7 +970,7 @@ static int pac_mask_get(struct task_struct *target, * depending on TCR_EL1.TBID*, which we may make use of in future, so * we expose separate masks. */ - unsigned long mask = ptrauth_pac_mask(); + unsigned long mask = ptrauth_pac_mask_ttbr0(); struct user_pac_mask uregs = { .data_mask = mask, .insn_mask = mask, diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index 4989f7ea1e59..44f6a64a8006 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -24,6 +24,7 @@ #include <linux/stacktrace.h> #include <asm/irq.h> +#include <asm/pointer_auth.h> #include <asm/stack_pointer.h> #include <asm/stacktrace.h> @@ -56,6 +57,8 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) frame->fp = READ_ONCE_NOCHECK(*(unsigned long *)(fp)); frame->pc = READ_ONCE_NOCHECK(*(unsigned long *)(fp + 8)); + frame->pc = ptrauth_strip_insn_pac(frame->pc); + #ifdef CONFIG_FUNCTION_GRAPH_TRACER if (tsk->ret_stack && (frame->pc == (unsigned long)return_to_handler)) { -- 2.11.0
next prev parent reply other threads:[~2018-10-05 8:50 UTC|newest] Thread overview: 161+ messages / expand[flat|nested] mbox.gz Atom feed top 2018-10-05 8:47 [PATCH 00/17] ARMv8.3 pointer authentication support Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 01/17] arm64: add pointer authentication register bits Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-11 16:28 ` Will Deacon 2018-10-11 16:28 ` Will Deacon 2018-10-12 8:53 ` Mark Rutland 2018-10-12 8:53 ` Mark Rutland 2018-10-12 8:56 ` Will Deacon 2018-10-12 8:56 ` Will Deacon 2018-10-12 9:50 ` Mark Rutland 2018-10-12 9:50 ` Mark Rutland 2018-10-05 8:47 ` [PATCH v5 02/17] arm64/kvm: consistently handle host HCR_EL2 flags Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 03/17] arm64/kvm: hide ptrauth from guests Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 04/17] arm64: Don't trap host pointer auth use to EL2 Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 05/17] arm64/cpufeature: detect pointer authentication Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 06/17] asm-generic: mm_hooks: allow hooks to be overridden individually Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 07/17] arm64: add basic pointer authentication support Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-11 16:00 ` Suzuki K Poulose 2018-10-11 16:00 ` Suzuki K Poulose 2018-10-19 11:15 ` Catalin Marinas 2018-10-19 11:15 ` Catalin Marinas 2018-10-19 11:15 ` Catalin Marinas 2018-10-19 11:24 ` Will Deacon 2018-10-19 11:24 ` Will Deacon 2018-10-19 15:36 ` Kees Cook 2018-10-19 15:36 ` Kees Cook 2018-10-19 15:36 ` Kees Cook 2018-10-19 15:49 ` Will Deacon 2018-10-19 15:49 ` Will Deacon 2018-10-19 15:49 ` Will Deacon 2018-10-19 16:05 ` Kees Cook 2018-10-19 16:05 ` Kees Cook 2018-10-19 16:05 ` Kees Cook 2018-10-19 16:16 ` Will Deacon 2018-10-19 16:16 ` Will Deacon 2018-10-19 16:16 ` Will Deacon 2018-10-19 15:54 ` Mark Rutland 2018-10-19 15:54 ` Mark Rutland 2018-10-19 15:54 ` Mark Rutland 2018-10-19 16:49 ` Cyrill Gorcunov 2018-10-19 16:49 ` Cyrill Gorcunov 2018-10-19 16:49 ` Cyrill Gorcunov 2018-11-14 18:11 ` Will Deacon 2018-11-14 18:11 ` Will Deacon 2018-11-15 10:25 ` Dave Martin 2018-11-15 10:25 ` Dave Martin 2018-10-23 8:36 ` Ramana Radhakrishnan 2018-10-23 8:36 ` Ramana Radhakrishnan 2018-10-23 8:36 ` Ramana Radhakrishnan 2018-10-23 8:36 ` Ramana Radhakrishnan 2018-10-23 10:20 ` Will Deacon 2018-10-23 10:20 ` Will Deacon 2018-10-23 10:20 ` Will Deacon 2018-10-23 10:20 ` Will Deacon 2018-10-05 8:47 ` [PATCH v5 08/17] arm64: expose user PAC bit positions via ptrace Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 09/17] arm64: perf: strip PAC when unwinding userspace Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 10/17] arm64: enable pointer authentication Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` [PATCH v5 11/17] arm64: docs: document " Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 9:04 ` Ramana Radhakrishnan 2018-10-05 9:04 ` Ramana Radhakrishnan 2018-10-05 9:04 ` Ramana Radhakrishnan 2018-10-16 16:14 ` Kristina Martsenko 2018-10-16 16:14 ` Kristina Martsenko 2018-10-16 16:14 ` Kristina Martsenko 2018-10-19 11:35 ` Catalin Marinas 2018-10-19 11:35 ` Catalin Marinas 2018-10-19 11:35 ` Catalin Marinas 2018-10-19 11:35 ` Catalin Marinas 2018-10-19 11:47 ` Marc Zyngier 2018-10-19 11:47 ` Marc Zyngier 2018-10-19 11:47 ` Marc Zyngier 2018-10-19 11:47 ` Marc Zyngier 2018-10-19 12:22 ` Will Deacon 2018-10-19 12:22 ` Will Deacon 2018-10-19 12:22 ` Will Deacon 2018-10-19 12:22 ` Will Deacon 2018-10-19 14:42 ` Kristina Martsenko 2018-10-19 14:42 ` Kristina Martsenko 2018-10-19 14:42 ` Kristina Martsenko 2018-10-19 14:42 ` Kristina Martsenko 2018-10-19 15:10 ` Catalin Marinas 2018-10-19 15:10 ` Catalin Marinas 2018-10-19 15:10 ` Catalin Marinas 2018-10-19 15:10 ` Catalin Marinas 2018-10-19 17:45 ` Will Deacon 2018-10-19 17:45 ` Will Deacon 2018-10-19 17:45 ` Will Deacon 2018-10-19 17:45 ` Will Deacon 2018-11-02 6:02 ` Jon Masters 2018-11-02 6:02 ` Jon Masters 2018-11-02 6:02 ` Jon Masters 2018-11-02 6:02 ` Jon Masters 2018-10-24 10:56 ` Ramana Radhakrishnan 2018-10-24 10:56 ` Ramana Radhakrishnan 2018-10-24 10:56 ` Ramana Radhakrishnan 2018-10-15 22:35 ` Kees Cook 2018-10-15 22:35 ` Kees Cook 2018-11-02 9:46 ` Ramana Radhakrishnan 2018-11-02 9:46 ` Ramana Radhakrishnan 2018-11-02 9:46 ` Ramana Radhakrishnan 2018-10-05 8:47 ` [RFC 12/17] arm64: move ptrauth keys to thread_info Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-19 11:38 ` Catalin Marinas 2018-10-19 11:38 ` Catalin Marinas 2018-10-05 8:47 ` [RFC 13/17] arm64: install user ptrauth keys at kernel exit time Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko [this message] 2018-10-05 8:47 ` [RFC 14/17] arm64: unwind: strip PAC from kernel addresses Kristina Martsenko 2018-10-05 8:47 ` [RFC 15/17] arm64: enable ptrauth earlier Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-06 12:51 ` Amit Kachhap 2018-10-06 12:51 ` Amit Kachhap 2018-10-05 8:47 ` [RFC 16/17] arm64: initialize and switch ptrauth kernel keys Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-06 12:56 ` Amit Kachhap 2018-10-06 12:56 ` Amit Kachhap 2018-10-05 8:47 ` [RFC 17/17] arm64: compile the kernel with ptrauth -msign-return-address Kristina Martsenko 2018-10-05 8:47 ` Kristina Martsenko 2018-10-05 9:01 ` Ramana Radhakrishnan 2018-10-05 9:01 ` Ramana Radhakrishnan 2018-10-05 9:01 ` Ramana Radhakrishnan 2018-10-11 14:00 ` Kristina Martsenko 2018-10-11 14:00 ` Kristina Martsenko 2018-10-11 14:00 ` Kristina Martsenko 2018-10-11 14:23 ` Vladimir Murzin 2018-10-11 14:23 ` Vladimir Murzin 2018-10-15 22:38 ` Kees Cook 2018-10-15 22:38 ` Kees Cook 2018-10-15 22:38 ` Kees Cook 2018-10-15 22:42 ` [PATCH 00/17] ARMv8.3 pointer authentication support Kees Cook 2018-10-15 22:42 ` Kees Cook 2018-11-13 16:17 ` Kristina Martsenko 2018-11-13 16:17 ` Kristina Martsenko 2018-11-13 23:09 ` Kees Cook 2018-11-13 23:09 ` Kees Cook 2018-11-14 15:54 ` Kristina Martsenko 2018-11-14 15:54 ` Kristina Martsenko 2018-11-14 21:47 ` Mark Rutland 2018-11-14 21:47 ` Mark Rutland 2018-11-14 22:48 ` Kees Cook 2018-11-14 22:48 ` Kees Cook 2018-11-14 22:48 ` Kees Cook 2018-10-19 12:36 ` Will Deacon 2018-10-19 12:36 ` Will Deacon 2018-10-23 8:39 ` Ramana Radhakrishnan 2018-10-23 8:39 ` Ramana Radhakrishnan 2018-10-23 8:39 ` Ramana Radhakrishnan 2018-10-23 8:39 ` Ramana Radhakrishnan
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